1. Field
Apparatuses consistent with exemplary embodiments relate to a piezoelectric linear actuator including an in-situ cleaning unit.
2. Description of the Related Art
To move a probe close to a sample in scanning probe microscopes (SPMs), very accurate linear actuators having a step less than several nanometers are needed. Linear actuators, including a shear piezo driven by a slip-stick motion, are used in SPMs for ultra-high vacuum low-temperatures.
Such a linear actuator may have a smooth contact surface for the slip-stick motion. If fine particles attach to the contact surface thereof, the linear actuator may malfunction.
Since SPMs for ultra-high vacuum are used under a vacuum condition, dust, etc. in the air does not attach to the contact surface. However, if fine particles separated from a sample or pieces separated from a probe tip are inserted between two surfaces for the slip motion, the linear actuator may malfunction. Particularly, in the case of low-temperature conditions, since a deformation range of the piezoelectric material is small, the possibility of malfunction may increase.
If this trouble arises, the linear actuator may be disassembled to clean the contact surface, and then the ultra-high vacuum may be created again. Thus, it may take a long time and be too cumbersome to perform these processes. Therefore, linear actuators, which can perform in-situ cleaning on slip surfaces, are desired.